The research performed in this project will provide specific binding molecules for the quantitation of opioid peptides, using an innovative scheme for synthesis, selection and analysis of peptide-binding structures. In Phase I, binding molecules will be synthesized by means of a novel templating technology. This technology involves coupling the target peptide to a solid support and building around it a polymer network that has many specific, noncovalent points of interaction with the peptide. Promising binding structures will be labeled with a fluorophore, and feasibility will be proven by coupling peptides to optical fibers and performing competitive binding assays using fluorescent-labeled binders. Solid state NMR analysis will indicate the degree of homogeneity of selected structures and, when coupled with the use of 13C-labeled template peptide, will suggest recognition groups that specifically interact with targeted functional groups on the peptide. In Phase II we will refine templating schemes, and use structural data from solid state NMR to interpolate consensus structures that can be prepared by solution chemistry, eliminating the need for templates in scaling up. We also will prepare binders that recognize additional opioid peptides, including peptide precursors, and use these binders to determine the activity of processing, enzymes. PROPOSED COMMERCIAL APPLICATION: These synthetic binders can provide features unavailable in conventional antibodies and receptors, including enhanced stability to enzymatic hydrolysis, reduced size, production without animals or tissue culture, ease of manufacturing scale-up and the resulting reduction in cost, nonimmunogenicity, and potential for use in non-aqueous solvents. These molecules can be adapted to any assay format, and have the potential for use in analytical and preparative separations, and for therapeutic applications.